Relationships between Pain Cognitions and Physical Function in a Sample of Racially Diverse, Sedentary Individuals with Chronic Pain

Abstract

Background:

Pain from musculoskeletal pain conditions is often persistent, bothersome, and negatively impacts physical function. Individuals with musculoskeletal pain report difficulty with walking and regular activities. For some, this may be related to overly negative pain cognitions, such as pain catastrophizing and kinesiophobia. In a geographically and racially diverse sample, we examined relationships between pain catastrophizing, kinesiophobia, and multimodal physical function (i.e., self-report, performance-based, objective).

Methods:

Participants were sedentary adults with ≥3 months of chronic musculoskeletal pain. Participants completed self-report measures of pain catastrophizing (Pain Catastrophizing Scale), kinesiophobia (Tampa Scale of Kinesiophobia), and physical function (World Health Organization Disability Assessment Scale 2.0). Performance-based physical function was assessed in-clinic with the Six-Minute Walk Test (6MWT). Physical function was objectively measured with ≥4 days of ActiGraph wear outside the clinic. We conducted descriptive, correlation, and linear regression statistics in SPSS.

Results:

Higher levels of pain catastrophizing (β=.42) and kinesiophobia (β=.25) were significantly associated with worse self-reported physical function. Neither pain catastrophizing nor kinesiophobia were related to performance-based or objectively measured physical function. The direction and significance of relationships between pain catastrophizing, kinesiophobia, and physical function measures were consistent in unadjusted and adjusted regression models.

Conclusions:

Pain catastrophizing and kinesiophobia are associated with an individual’s perceived physical functioning. Behavioral interventions designed to enhance physical function may benefit from including cognitive restructuring to challenge catastrophic thoughts about pain, as well as thoughts about injuring oneself or worsening pain with movement. More work is needed to understand why neither pain catastrophizing nor kinesiophobia were significantly associated with performance-based or objective assessment of physical function. It is possible that other pain-related cognitions, for example self-efficacy for pain control, or variables (e.g., in-vivo pain catastrophizing, mood, stress, sleep) assessed closer in time to performance-based or objective measures of physical function are more relevant.

Introduction

Individuals with musculoskeletal pain conditions describe their pain as persistent, bothersome, and interfering to functioning.^1–3 Physical activity can be difficult for individuals with musculoskeletal pain conditions due to negative pain cognitions (i.e., the way one thinks about their pain).^4–7 The Fear Avoidance Model outlines how disabling chronic pain is perpetuated through a spiral of negative pain cognitions, avoidance, and decreased activity.^8–10 Walking is typically the most acceptable form of physical activity reported by individuals with chronic pain, and is unlikely to cause harm.^4,6 However, many individuals with chronic pain have negative pain-related thoughts that interfere with walking and fear that walking might further increase pain, resulting in suboptimal uptake and adherence to daily walking guidelines.^4–7,11,12 Patients with chronic pain are often sedentary (i.e., <5,000 steps per day¹³), taking fewer daily steps than is recommended for good health (approximately 10,000 steps per day).^4,5,14–16

Two pain-related cognitions that may be particularly influential on attitudes toward walking are pain catastrophizing and kinesiophobia. Pain catastrophizing is the tendency to fixate on and magnify pain sensations, and feel helpless when faced with pain (e.g., “I can’t stop thinking about how much it hurts”).¹⁷ Kinesiophobia refers to cognition around the fear of pain and activities that are perceived to increase pain (e.g., “I’m afraid I might injure myself if I walk”).¹⁸ Many studies using self-report measures have shown that higher levels of pain catastrophizing and kinesiophobia are associated with higher pain severity and interference, psychological distress, and disability among individuals with musculoskeletal pain.^19–23 There is less consensus on the relationships of pain catastrophizing and kinesiophobia to performance-based and objective measures of physical function. Performance-based measures of physical function (e.g., walking activity) typically assess functional capacity during a time-limited standard test in a monitored clinic setting, for example, the Six-Minute Walk Test (6MWT).^24,25 Objective measures of physical function often include accelerometers (e.g., ActiGraph^26,27) that index ambulatory step-count outside the clinic across a specified time period, usually a week.

The literature is mixed with respect to the relationship of both pain catastrophizing and kinesiophobia to performance-based and objective measures of physical function. Some studies report an association between pain catastrophizing and walking, measured with either the 6MWT or accelerometer.^23,28,29 This work, however, has been conducted in samples of patients having a similar diagnosis (e.g. women with fibromyalgia, older adults with osteoarthritis) and that are relatively homogeneous in age, race, and sex. Interestingly, pain catastrophizing has not been found to be related to performance-based or objectively measured walking in studies that have patient samples with mixed pain conditions.^30,31 Research investigating the relationship of kinesiophobia to performance-based and/or objective measures of walking is similarly inconsistent.^29,30 In a study of patients with lumbar stenosis but unclear duration of chronic pain, Minetama and colleagues (2022) found that pain anxiety symptoms (e.g., “I will stop any activity as soon as I sense pain coming on”) predicted daily pedometer step count, while kinesiophobia did not. Other work with patients reporting mixed chronic pain conditions has also not found a significant relationship between kinesiophobia and performance-based and/or objective measures of physical function.³¹

In addition to this lack of clarity, extant research does not often examine pain catastrophizing and kinesiophobia as independent variables in the same model predicting self-report, performance-based, and objective measures of physical function.²⁹ This is a missed opportunity to enhance our understanding of the unique contributions these pain cognitions have on multimodal assessment of physical function. Findings could have particular relevance to the development of behavioral pain interventions wherein pain catastrophizing and kinesiophobia are proposed mechanisms of change.^32–34 Further, it is plausible that pain catastrophizing and kinesiophobia exhibit differential effects depending on the type of physical function assessment (i.e., self-report, performance-based, objective).^31,35 If pain catastrophizing and kinesiophobia are associated with self-reported physical function but not objectively measured walking activity, this will have implications for how behavioral pain interventions target such outcomes. For example, objectively measured walking activity might be more responsive to behavioral techniques that leverage pacing (e.g., quota-based contingent walking schedules, activity-rest cycle), goal setting, and positive reinforcement, as opposed to cognitive-restructuring techniques focused on changing negative pain cognitions.

To address these inconsistencies in the literature, we conducted a secondary analysis of baseline data from a multi-site trial (N=92) examining the feasibility of a mind-body activity intervention for pain.³⁶ Unlike prior studies, our participants were geographically and racially diverse, sedentary adults with heterogenous pain conditions and chronic pain lasting from three to ten years. We aimed to evaluate the relationships between pain cognitions (i.e., pain catastrophizing, kinesiophobia) and multimodal assessment of physical function (i.e., self-report, performance, objective). We hypothesized that participants endorsing higher levels of pain catastrophizing and kinesiophobia would demonstrate worse physical function. Pain catastrophizing and kinesiophobia were included in the same model to explore their unique predictive value when compared against each other. Second, in an exploratory aim, we investigated whether pain catastrophizing and kinesiophobia show different relations to physical function depending on the type of physical function assessment (i.e., self-report, performance-based, objective).

Methods

Participants

Eligible participants (N=92) were English-speaking adults ≥18 years of age with chronic musculoskeletal pain (i.e., ≥3 months of non-malignant pain³⁷) as identified in the medical record. Other inclusion criteria were 1) ability to walk for at least 6 minutes, 2) free of concurrent psychotropic or pain medication, or stable on current medication for a minimum of 6 weeks and willing to maintain a stable dose, 3) owns a smartphone or computer with Bluetooth capabilities, and 4) sedentary, as measured by meeting 2 of 3 self-reported markers: [1] sits for ≥8 hours per day, [2] exercises <3 days per week (30+ minutes of intentional exercise), and/or [3] walks <7 days per week (30+ minutes of walking). Exclusion criteria included 1) diagnosed medical illness expected to worsen in the next 6 months, 2) serious, untreated mental illness (e.g., active suicidal ideation, bipolar disorder, schizophrenia, substance use) for which hospitalization may occur, 3) unable to walk and/or in a wheelchair, 4) practice of yoga, meditation, or related mind-body techniques for 45+ minutes per week for the last three months, 5) regular use of a smartwatch (i.e., Fitbit, Apple Watch) and unwillingness to discontinue use for the duration of the study, and (6) suspected cognitive impairment confirmed by ≥4 errors on the Short Portable Mental Status Questionnaire.

Procedures

The parent study was a multi-site trial examining the feasibility of a mind-body pain intervention.³⁶ Procedures at all three sites complied with HIPAA and were approved by respective Institutional Review Boards. Participants were recruited via referrals from established provider partnerships at pain clinics and medical record review. IRB-approved flyers were placed in approved areas (i.e., outpatient clinics, community health centers, in the community) and distributed to chronic pain Facebook groups and site-specific recruitment websites; an online research participant recruitment platform). Interested and potentially eligible participants were screened by study staff via telephone or REDCap survey. Eligible participants reviewed the consent form and were then scheduled for an in-person baseline assessment approximately 7–10 days before the intervention start date. At the baseline assessment, participants completed informed consent, self-report questionnaires (e.g., pain catastrophizing, kinesiophobia, physical function, and demographic and clinical characteristics), the Six-Minute Walk Test (6MWT), and were given an ActiGraph to wear for one week. The present study is a secondary analysis of these baseline data. Further details about the study protocol have been previously published.³⁶

Measures

Pain Catastrophizing.

Pain Catastrophizing was assessed using the 13-item Pain Catastrophizing Scale (PCS).³⁸ The PCS evaluates hopelessness, helplessness, and rumination about pain. Participants rate the degree to which they have certain thoughts (e.g., “I can’t stop thinking about how much it hurts,” “I’m afraid that something serious might happen”) using a 5-point scale ranging from 0 (Never) to 4 (Always). Individual items are summed for a total score that ranges from 0 to 52, with higher scores indicating increased pain catastrophizing. The PCS is used widely in chronic pain research and exhibits strong validity and reliability.^39–41

Kinesiophobia.

Fear of activity due to pain (e.g., “If I were to try to overcome it, my pain would increase”) or injury (“I’m afraid I might injure myself if I exercise”) was measured using the 17-item Tampa Scale of Kinesiophobia (TSK).⁴² Items are scored on a scale from 1 (Strong Disagree) to 4 (Strongly Agree) and summed for a total score that ranges from 17 to 68, with higher scores reflecting more severe kinesiophobia. The TSK is considered a gold-standard measure of kinesiophobia in adults with chronic pain conditions and demonstrates sound psychometric properties.^43,44

Physical Function.

Self-Report. Participant’s self-reported physical function was assessed with the 36-item World Health Organization Disability Assessment Scale (WHODAS 2.0).⁴⁵ The WHODAS 2.0 evaluates difficulties in six main areas of physical function (i.e., cognition, walking/mobility, self-care, getting along, life activities, and participation). Items are rated on a scale from 0 (None) to 4 (Extreme/Cannot Do) and averaged to obtain subscale scores and a total score that ranges from 0 to 4, with higher scores reflecting more difficulty with physical function. The WHODAS 2.0 shows adequate validity and reliability in adults with chronic pain conditions.⁴⁶ Performance-based. Participants completed the Six-Minute Walk Test (6MWT), a self-paced, timed test of total distance (meters) walked in six minutes. The 6MWT was administered in a monitored clinic setting according to the American Thoracic Society guidelines.^24,25 Objective. Participants received an ActiGraph wGT3X-BT^26,27 to wear in their home environment for one week. Participants were instructed to wear the device on their non-dominant hand at all times except when bathing or swimming, and settings were customized based on participant height. Participants were considered compliant and “cleared” to return the device if they tracked ≥4 days of valid wear data (>10 waking hours/day). Participants with <4 days continued to wear the device until reaching the 4-day threshold.

Demographic and Clinical Variables.

Demographic and clinical data were collected by participant self-report and electronic medical record review. Demographic data included: age, sex, race, ethnicity, partner status, education, and employment. Clinical information included: body mass index (BMI), type(s) of pain, duration of chronic pain, pain medication use, and comorbid psychiatric conditions.

Analytic Plan

Analyses were conducted using Statistical Package for the Social Sciences (SPSS Version 29). Spearman correlation coefficients demonstrated the pairwise relationships among main study variables (Table 3). Linear regressions assessed the relationships between pain cognitions and physical function, before and after controlling for theoretically-supported covariates (i.e., age, sex, race).^47–49 Physical function was indexed by 1) self-reported total score on the WHODAS 2.0, 2) total distance (meters) walked during the 6MWT, and 3) average daily step-count taken from participants’ ActiGraph. The unique predictive value of pain catastrophizing and kinesiophobia on walking activity (i.e., self-report, performance-based, objective) was examined by interpreting the absolute value of the standardized parameter estimates.

Table 3.

Means (M), Standard Deviations (SD), and Correlation Matrix for Main Study Variables

Variable	Pain Catastrophizing	Kinesiophobia	Physical Function WHODAS	Physical Function 6MWT	Physical Function ActiGraph
N	92	86	87	91	90
M (SD)	20.10 (12.39)	40.16 (5.57)	1.34 (0.68)	276.09 (77.96)	2903.32 (2190.03)
Range	0 – 52	17 – 68	0 – 4	34 – 462	79 – 10127
Pain Catastrophizing	1	-	-	-	-
Kinesiophobia	.22*	1	-	-	-
WHODAS	.47**	.34**	1	-	-
6MWT	−.09	−.16	.20	1	-
ActiGraph	.15	−.05	−.05	.24*	1

Note. N does not equal 92 due to missing data; M=mean; SD=standard deviation; WHODAS=World Health Organization Disability Assessment Scale 2.0; 6MWT=Six-Minute Walk Test; 6MWT measured in meters; Actigraph=average daily step count;

^*p<.05;

^**p<.01.

Results

Participant Characteristics

Participants were 56.6 years old on average (range: 23 – 92) and mostly female (75.0%) and Non-Hispanic (83.7%). Nearly half the sample identified as Black/African-American (44.6%). Most common types of chronic pain were muscle (e.g., myalgia; 76.1%) and joint pain (e.g., arthritis; 69.6%). At consent, 47.8% of participants reported experiencing chronic pain for 3 to 10 years. Additional demographic and clinical characteristics are reported in Tables 1 and 2.

Table 1.

Demographic Characteristics (N=92)

	N (%)	M (SD)
Age (years)		56.58 (14.37)
Sex
Male	23 (25.0%)
Female	69 (75.0%)
Race
White/Caucasian	37 (40.2%)
Black/African American	41 (44.6%)
American Indian or Alaskan Native	0 (0.0%)
Asian	2 (2.2%)
Native Hawaiian or Other Pacific Islander	0 (0.0%)
More than One Race	8 (8.7%)
Ethnicity
Non-Hispanic	77 (83.7%)
Hispanic or Latino	5 (5.4%)
Partner Status
Single, Never Married	29 (31.5%)
Married	30 (32.6%)
Separated or Divorced	16 (17.4%)
Widowed	9 (9.8%)
Living with Significant Other	3 (3.3%)
Education
Less than High School (<12 years)	2 (2.2%)
Completed High School or GED (12 years)	18 (19.6%)
Some College/Associate’s Degree (<16 years)	28 (30.4%)
Completed College/Bachelor’s Degree (16 years)	25 (27.2%)
Graduate/Professional Degree (>16 years)	15 (16.3%)
Employment
Employed Full-Time	21 (22.8%)
Employed Part-Time	7 (7.6%)
Keeping House/Housemaker	5 (5.4%)
Going to School Full- or Part-Time	0 (0.0%)
Retired	30 (32.6%)
Unemployed	13 (14.1%)
Other	9 (9.8%)

Note. M=mean; SD=standard deviation. Percentages do not sum to 100% due to missing data.

Table 2.

Clinical Characteristics (N=92)

	N (%)	M (SD)
BMI		32.11 (7.66)
Types of Chronic Pain (% yes)
Muscle Pain (e.g., Myalgia)	70 (76.1%)
Bone Pain (e.g., Osteoporosis)	39 (42.4%)
Tendon or Ligament Pain (e.g., Tendinitis)	38 (41.3%)
Joint Pain (e.g., Arthritis)	64 (69.6%)
Other	27 (29.3%)
Duration of Chronic Pain
3 – 5 Months	0 (0.0%)
6 – 11 Months	1 (1.1%)
1 Year – Less than 3 Years	10 (10.9%)
3 Years – Less than 10 Years	44 (47.8%)
More than 10 Years	36 (39.1%)
Medications (% yes)
OTC (e.g., Tylenol, Advil, Aleve)	67 (72.8%)
Opioids (e.g., hydrocodone, Vicodin)	13 (14.1%)
Neurontin	10 (10.9%)
Pregabalin (e.g., Lyrica)	12 (13.0%)
Topiramate	3 (3.3%)
Antidepressants (e.g., amitriptyline, Cymbalta)	28 (30.4%)
Marijuana/THC	15 (16.3%)
CBD	10 (10.9%)
Other	32 (34.8%)
None	5 (5.4%)
Psychiatric Conditions (% yes)
Depression	31 (33.7%)
Anxiety	32 (34.8%)
PTSD	17 (18.5%)
Other	7 (7.6%)

Note. M=mean; SD=standard deviation; BMI=body mass index; OTC=over-the-counter; THC=Tetrahydrocannabinol; CBD=Cannabidiol; PTSD=post-traumatic stress disorder. Percentages do not sum to 100% due to missing data.

Descriptive Statistics and Correlations for Main Study Variables

Descriptive and correlation statistics are shown in Table 3. Higher levels of pain catastrophizing were associated with higher kinesiophobia (r=.22, p<.05) and worse physical function on the WHODAS 2.0 (r=.47, p<.01); likewise, higher levels of kinesiophobia were associated with worse physical function on the WHODAS 2.0 (r=.34, p<.01). Neither type of pain cognition (i.e., pain catastrophizing, kinesiophobia) was significantly associated with 6MWT distance or average daily ActiGraph steps. Performance on the 6MWT and daily ActiGraph step measure were associated with each other (r=.24, p<.05), however, neither of these measures were significantly correlated with physical function as indexed by the self-reported WHODAS 2.0.

Linear Regressions

In an unadjusted model, both pain catastrophizing (B=.02, p<.001, 95% CI [.01, .03]) and kinesiophobia (B=.03, p=.02, 95% CI [.01, .05]) were significantly associated with physical function on the WHODAS 2.0, with standardized parameters suggesting a larger association for pain catastrophizing (β=.42) versus kinesiophobia (β=.25). Significant associations held after covariates (i.e., age, sex, race) were added to the model; higher pain catastrophizing and kinesiophobia were related to worse self-reported physical function on the WHODAS 2.0, with pain catastrophizing (β=.25) still exhibiting a stronger standardized effect than kinesiophobia (β=.20). Table 4 shows adjusted model statistics.

Table 4.

Adjusted Regression Models

	Model 1				Model 2				Model 3
	Physical Function WHODAS				Physical Function 6MWT				Physical Function ActiGraph
	B	p	95% CI	β	B	p	95% CI	β	B	p	95% CI	β
Pain Catastrophizing	.01	.013	.00,.02	.25	−1.33	.062	−2.72,.07	−.21	8.62	.627	−26.52,43.75	.05
Kinesiophobia	.02	.040	.00,.44	.20	−2.93	.056	−5.94,.08	−.20	−31.52	.395	−104.85,41.82	−.09
Covariates
Age	−.01	.042	−.02,.00	−.20	−2.21	<.001	−3.37,−1.05	−.41	−40.40	.005	−68.50,−12.30	−.32
Sex	.49	<.001	.23,.75	.34	6.24	.736	−30.55,43.02	.03	−1337.94	.004	−2240.77,−435.11	−.31
Race	−.23	.070	−.47,.02	−.17	−35.46	.040	−69.35,−1.58	−.22	380.49	.358	−439.49,1200.46	.10

Note. WHODAS=World Health Organization Disability Assessment Scale 2.0; 6MWT=Six-Minute Walk Test; 6MWT measured in meters; Actigraph=average daily step count; Sex was categorized 0=Male vs. 1=Female; Race was categorized 0=White vs. 1=Minority; Unstandardized (B) and standardized estimates (β); p-values and 95% confidence interval (CI) for unstandardized estimates.

In an unadjusted model, neither pain catastrophizing (B=−.29, p=.68, 95% CI [−1.69, 1.10], β=−.05) nor kinesiophobia (B=−2.06, p=.20, 95% CI [−5.19, 1.08], β=−.15) were significantly associated with physical function when assessed by the 6MWT. Once covariates were added to the model, relationships strengthened indicating that more pain catastrophizing (B=−1.33, p=.06, 95% CI [−2.72, .07], β=−.21) and kinesiophobia (B=−2.93, p=.06, 95% CI [−5.94, .08], β=−.05) were associated with less distance walked during the 6MWT. These relationships were close to, but did not reach significance at the p<.05 level. Pain catastrophizing (B=34.99, p=.07, 95% CI [−3.52, 73.50]), β=.20) and kinesiophobia (B=−34.35, p=.42, 95% CI [−118.28, 49.58]), β=−.09) were both not significantly associated with physical function when assessed by ActiGraph, and these non-significant relationships remained after covariates were added to the models (Table 4).

Discussion

This was a cross-sectional analysis of data from a multi-site trial examining the feasibility of a mind-body pain intervention for geographically and racially diverse, sedentary adults with heterogenous chronic pain. We aimed to evaluate the relationships between pain cognitions (i.e., pain catastrophizing, kinesiophobia) and physical function, assessed via self-report, performance-based, and objective measures. Additionally, we explored whether pain catastrophizing and kinesiophobia show different relationships to physical function depending on the type of physical function assessment (i.e., self-report, performance-based, objective).

In partial support of our hypothesis, we observed that pain catastrophizing and kinesiophobia were significantly associated with self-reported physical function. Specifically, higher pain catastrophizing and higher kinesiophobia were associated with worse physical function. These associations held after controlling for relevant covariates (e.g., age, sex, race). Of note, we assessed pain cognitions together in one model to determine their association with physical function when compared against each other. Although kinesiophobia was related to self-reported physical function, the standardized parameter estimate for pain catastrophizing was larger than that of kinesiophobia suggesting that pain catastrophizing has a stronger association with self-reported physical function. This is a novel extension of previous work and offers a more nuanced understanding of the role of pain cognitions.^29,31,35 It is possible that pain catastrophizing showed a stronger association with self-reported physical function in this study because the WHODAS 2.0 measures difficulties with functioning across six different areas (e.g., cognition, walking/mobility, self-care, getting along, life activities, and participation), all of which may be impacted by pain catastrophizing. Conversely, kinesiophobia, might be more directly related to self-reported mobility specifically, rather than a broad assessment of functioning across multiple domains, some of which do not involve much or any movement (e.g., cognition). It is worth noting that once covariates were added to the model, standardized parameter estimates for pain catastrophizing and kinesiophobia were closer in absolute value, suggesting that perhaps these pain cognitions hold relatively equal weight with respect to self-reported physical functioning. In their topical review, Wideman et al. (2013) suggest as much, hypothesizing pain catastrophizing and kinesiophobia likely have additive, versus distinct, effects on pain-related disability.¹²

In unadjusted models, neither pain catastrophizing nor kinesiophobia was significantly related to performance-based or objectively measured physical function. Notably, once covariates were included, associations of higher pain catastrophizing and kinesiophobia to less 6MWT distance strengthened (ps =.06), though still did not reach statistical significance. It is possible that in a larger, fully powered sample, such relationships would be more apparent. Nevertheless, in the present study, self-reported pain cognitions were not related to performance-based or objective measures of physical function. One potential explanation for this finding is common method variance across self-report independent and dependent measures (i.e., pain catastrophizing, kinesiophobia, WHODAS 2.0) inflating associations between these variables. The lack of relationship between self-report and performance-based and/or objective measures has been observed previously,^31,51,52 and our results add to a body of literature supporting the hypothesis that self-report measures of symptoms and function do not consistently relate to performance-based and/or objective measures of those same constructs.

Another possible explanation for observed null relationships between pain cognitions and performance-based and objective measures of physical function is misaligned assessment timeframe. At the baseline appointment, participants were asked to report on pain catastrophizing and kinesiophobia, generally, “when in pain.” Perhaps if participants were asked to rate pain catastrophizing and kinesiophobia in relation to the 6MWT specifically, or a defined period of walking while wearing the ActiGraph (see Situational Pain Catastrophizing Scale [SPCS]⁵³), we might observe stronger associations between these pain cognitions and performance-based or objectively measured physical function.⁵⁴ Additionally, performance on the 6MWT and/or average daily step count may be most strongly associated with factors closer in time to those performance-based and/or objective assessments; for instance, an individual’s mood, diet, sleep, and/or stress level on the day of assessment.

A strength of the parent study was its multi-site design, yielding a sample of geographically and racially diverse (44.6% Black/African-American) participants with mixed pain type and considerable chronic pain duration (39.1% reporting ≥10 years of pain). However, participants were predominately female and the sample size for this feasibility trial was rather modest and thus likely underpowered to detect small-medium effects between self-report and performance-based and/or objective measures. The parent study did not include a measure of self-efficacy for pain control, or confidence in one’s ability to manage pain symptoms without medical intervention. Though also measured via self-report, it may be that self-efficacy for pain management is more strongly associated with performance on the 6MWT and/or average daily step count indexed by actigraphy. Future work might consider including pain catastrophizing, kinesiophobia, and self-efficacy for pain management in regression models to determine their unique impact on multimodal assessment of physical function.

There are several meaningful clinical implications of this work. We found that both pain catastrophizing and kinesiophobia were associated with self-reported physical function, though pain catastrophizing may be more strongly associated with this outcome. Behavioral pain interventions designed to increase walking should consider including skills such as cognitive restructuring to identify, challenge, and change catastrophic thoughts about pain (e.g., “I will always be in pain”), as well as thoughts about worsening pain with movement (“I will injure myself if I walk outside”). Negative pain cognitions are likely important drivers of change in clinical pain trial outcomes such as self-reported pain and disability.^32–34 Pain catastrophizing and kinesiophobia were not significantly associated with performance-based and objective assessment of walking; more well-powered, longitudinal research is needed to further elucidate these relationships since trends towards significance were observed here. It is plausible that an individual’s confidence in their ability (i.e., self-efficacy) to engage in regular physical activity is most relevant to performance-based and objectively measured walking, versus rumination on, or fear of pain.^55,56 If so, behavioral strategies that emphasize pacing (e.g., quota-based contingent walking schedules, activity-rest cycle), goal setting, and positive reinforcement are critical to include in programs aimed at improving both self-reported and performance-based and objective measures of pain and physical function. The most potent pain management interventions will likely need to incorporate both cognitive and behavioral techniques for challenging negative pain cognitions that influence one’s perception of their physical functioning, as well as behavioral skills that allow for real-world testing and strengthening of physical abilities.

Data Availability:

The data that support the findings of this study are available from the corresponding author upon reasonable request.